The US has maintained a migrant detention facility there for decades that is separate from the notorious high-security jail for foreign terror suspects, including alleged 9/11 mastermind Khalid Sheikh Mohammed.

President Trump says the the 30,000-person facility for undocumented migrants will house "the worst criminal illegal aliens".

Prominent rights groups and attorneys representing detainees at the Guantanamo Bay prison in Cuba have condemned a call by US President Donald Trump to use the notorious detention facility to house upwards of 30,